The Northern League was once a strong ally of former Prime Minister Silvio Berlusconi, but it has sought to find new allies as he struggles to shake off a tax fraud conviction that forced him out of parliament.

Mr Salvini's fiery rhetoric against the European Union, immigration and austerity politics had led to comparisons being drawn between him and French National Front leader Marine Le Pen.

The counter-demonstration staged by an alliance of leftist parties, anti-racism campaigners and gay rights groups was held only a few hundred metres from the Northern League rally.

Many protested under the banner "Never with Salvini".

'Foolish servant'

"The problem isn't Renzi, Renzi is a pawn, Renzi is a dumb slave, at the disposal of some nameless person who wants to control all our lives from Brussels," Mr Salvini told the rally at the Piazza del Popolo.

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Police blocked streets leading to the square, determined to keep marchers in a counter-demonstration from clashing with Mr Salvini's supporters in Piazza del Popolo

Image copyrightAFPImage caption
Those at the counter-demonstration included leftist groups, anti-racism campaigners and gay rights groups

He told his supporters that the prime minister was the "foolish servant" of Brussels.

Mr Salvini spoke of a "different Europe, where banks count for less, and citizens and small businessmen count for more".

"I want to change Italy. I want the Italian economy to be able to move forward again, something that is obstructed by Brussels and mad European policies," he said, describing the government's immigration policies as "a disaster".

The two protests come just over two months ahead of regional elections in May.

Analysts say Mr Salvini could emulate other right-wing European leaders and capitalise on growing resentment against immigration, especially after recent attacks by Islamic extremists and the influx of migrants brought to Italy by Libyan-based smugglers.